SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '08cc5c80a0f83636c6e3bd6a2aa59b227647a65b150eadd3aca69d8d9416a1a0' 
  AND token = 'nCM1AAItCL0WtRKIPGVRvoBSypb1yk3SfzDhlV7CNkE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00052

JSON explain

{
  "query_block": {
    "select_id": 1,
    "message": "no matching row in const table"
  }
}